Modified propylene polymer composition and process of making composition

Abstract

A modified propylene polymer having superior coloring-prevention properties is provided by a process which comprises blending a propylene polymer with (A) a polyol or a fatty acid partial ester of the polyol (B) a phenolic antioxidant and (C) a radical generating agent with a propylene polymer containing 5 ppm or more of titanium or 0.5 ppm or more of vanadium as a catalyst residue and subjecting the resultant blend to a melting and kneading treatment at a temperature of 150 DEG C.-300 DEG C.

What we claim is: 
     
       1. The method which comprises (1) blending 100 parts by weight of a high catalyst residue propylene polymer containing at least 5 ppm of titanium in the form of a catalyst residue or at least 0.5 ppm vanadium in the form of a catalyst residue with (a) 0.014-1 parts by weight of a polyol or a partial ester of a polyol with a fatty acid,   (b) 0.01-1 parts by weight of a phenolic antioxidant, and   (c) 0.001-0.5 parts by weight of a radical generating agent, and     (2) subjecting said blend to melting and kneading at a temperature of 150° C.-300° C.   
     
     
       2. A method according to claim 1 wherein (a) is trimethylolethane, a monoester of glycerine with a fatty acid, a monoester of pentaerythritol with a fatty acid, or a diester of pentaerythritol with a fatty acid. 
     
     
       3. The method of claim 1 in which said phenolic antioxidant is 2,6-di-t-butyl-p-cresol, tetrakis[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate] methane, 1,3,5-tris (3,5-di-t-butyl-4-hydroxybenzyl)-isocyanurate or noctadecyl-beta-(4'-hydroxy-3',5'-di-6-butylphenyl)propionate. 
     
     
       4. The method of claim 1 in which said radical generating agent is 2,5-di-methyl-2,5-di-(t-butyl peroxy) hexane-2,5-dimethyl-2,5-di-(t-butyl peroxy)hexyne-3 or 1,3-bis-(6-butyl peroxy isopropyl)benzene. 
     
     
       5. The method of claim 1 in which said propylene polymer is propylene homopolymer, crystalline ethylene-propylene random copolymer, crystalline ethylene-propylene block copolymer, crystalline propylene-butene-1 random copolymer or crystalline ethylene-propylene-butene-1, terpolymer. 
     
     
       6. A method according to claim 1 wherein said propylene polymer is selected from the group consisting of propylene homopolymers and crystalline copolymers of propylene. 
     
     
       7. The method which comprises (1) blending 100 parts by weight of a propylene polymer containing at least 5 ppm of titanium in the form of a catalyst residue or at least 0.5 ppm vanadium in the form of a catalyst residue, said propylene polymer being selected from the group consisting of a propylene homopolymer, a crystalline ethylene-propylene random copolymer, a crystalline ethylene-propylene block copolymer, a crystalline propylene-butene-1 random copolymer and a crystalline ethylene-propylene-butene-1, terpolymer, with (a) 0.01-1 parts by weight of either a trimethylolethane, a monoester of glycerine with a fatty acid, a monoester of pentaerythritol with a fatty acid or a diester of pentaerythritol with a fatty acid, and   (b) 0.01-1 parts by weight of a phenolic antioxidant, selected from the group consisting of 2,6-di-t-butyl-op-cresol, tetrakis[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate] methane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene, 1,3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl)-isocyanurate and n-octadecyl-beta-(4'hydroxy-3',5'-di-t-butylphenyl) propionate, and     (2) subjecting said blend to melting and kneading at a temperature of 150° C.-300° C.   
     
     
       8. A method according to claim 1 wherein said melting and kneading treatment temperature is 180°-270° C. 
     
     
       9. A method according to claim 1 wherein a phosphorous-containing antioxidant is also added to the blend. 
     
     
       10. The product produced according to the method of claim 1. 
     
     
       11. The product produced according to the method of claim 2. 
     
     
       12. The product produced according to the method of claim 3. 
     
     
       13. The product produced according to the method of claim 4. 
     
     
       14. The product produced according to the method of claim 5. 
     
     
       15. The product produced according to the method of claim 6. 
     
     
       16. The product produced according to the method of claim 7. 
     
     
       17. The product produced according to the method of claim 8. 
     
     
       18. The product produced according to the method of claim 9. 
     
     
       19. A method according to claim 1 wherein (a) is glycerin monostearate. 
     
     
       20. The product produced according to the method of claim 19.